code: def test_HandleUnknown_HaveOnlyKnown_ExpectSecondColumn(self):
      train = ["A", "B"]
  
      encoder = encoders.PolynomialEncoder(handle_unknown="indicator")
      result = encoder.fit_transform(train)
  
      expected = [a_encoding, b_encoding]
      self.assertEqual(
          deep_round(result.to_numpy().tolist()), deep_round(expected)
      )
  
file_path: category_encoders/tests/test_polynomial.py
imports: import pandas
  from unittest import TestCase
  import numpy
  import category_encoders
  from tests.helpers import deep_round
label_desc: Use image node_id 11 for calling the TestPolynomialEncoder obj's underlying member method code with example usage: obj.test_HandleUnknown_HaveOnlyKnown_ExpectSecondColumn() without return types